首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   103552篇
  免费   9882篇
  国内免费   4955篇
耳鼻咽喉   2630篇
儿科学   511篇
妇产科学   1821篇
基础医学   11650篇
口腔科学   3420篇
临床医学   8143篇
内科学   13610篇
皮肤病学   2028篇
神经病学   441篇
特种医学   4956篇
外国民族医学   123篇
外科学   15454篇
综合类   18043篇
现状与发展   23篇
预防医学   2468篇
眼科学   497篇
药学   5394篇
  22篇
中国医学   1272篇
肿瘤学   25883篇
  2024年   205篇
  2023年   1554篇
  2022年   3100篇
  2021年   4068篇
  2020年   3576篇
  2019年   3297篇
  2018年   3167篇
  2017年   3584篇
  2016年   4098篇
  2015年   4649篇
  2014年   6974篇
  2013年   6118篇
  2012年   6208篇
  2011年   6714篇
  2010年   5495篇
  2009年   5299篇
  2008年   5506篇
  2007年   5731篇
  2006年   5352篇
  2005年   4745篇
  2004年   3774篇
  2003年   3336篇
  2002年   2796篇
  2001年   2684篇
  2000年   2259篇
  1999年   1858篇
  1998年   1672篇
  1997年   1527篇
  1996年   1327篇
  1995年   1146篇
  1994年   1043篇
  1993年   742篇
  1992年   641篇
  1991年   580篇
  1990年   487篇
  1989年   424篇
  1988年   405篇
  1987年   340篇
  1986年   267篇
  1985年   295篇
  1984年   250篇
  1983年   174篇
  1982年   200篇
  1981年   168篇
  1980年   158篇
  1979年   121篇
  1978年   93篇
  1977年   65篇
  1976年   59篇
  1975年   20篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
BACKGROUND: Basal cell carcinoma (BCC) is a non-melanoma form of skin cancer that is frequently localized within the cervicofacial area. So far, little research is available on how patients perceive their facial aesthetics after surgical treatment for BCC. OBJECTIVES: To analyse (i) if there was a statistically significant improvement over time with regard to the perceived facial aesthetics of surgical patients; (ii) if there was a significant difference between primary and recurrent BCC patients; and (iii) between patients who had Mohs micrographic surgery (MMS) or surgical excision (SE). To assess (iv) which baseline perceptions and/or clinical parameters may predict the evaluation of facial aesthetics at 6 months after surgery. METHODS: Parallel to a clinical trial, a survey was carried out in which patients were asked, by means of a newly developed disease-specific questionnaire, about perceptions with regard to their facial aesthetics before and after surgery. RESULTS: Aesthetic perceptions of all surgical patients improved over time. There was no statistically significant difference on facial aesthetics between the group with a primary or recurrent BCC and patients treated with MMS or SE. Results also showed that the evaluation of postsurgical facial aesthetics can be predicted by both visibility of the tumour and preoperative perceptions. CONCLUSION: It is recommended to administer preoperatively a short questionnaire in which perceptions related to facial aesthetics are included. In doing so, physicians will become more familiar with the aesthetic problems patients might have regarding their afflicted facial site. Ultimately, it may help physicians in deciding whether patients will benefit from additional cosmetic procedures after surgery.  相似文献   
83.
The aim of this prospective randomized study was to determine whether additional doxorubicin chemotherapy improves outcome in patients with hepatocellular carcinoma (HCCA) treated by liver transplantation. Stratification parameters were tumor stage (UICC I-IVa), gender, age 50 years, α-fetoprotein 20 ng/mL, cirrhosis and HbsAg status. For pre-operative chemotherapy doxorubicin (15 mg/m2) was given biweekly, intra-operative chemotherapy was a single dose administered before surgical manipulation. Post-operative chemotherapy from day 10 was as given preoperatively for a total dosage of 300 mg/m2. Outcome parameters were overall survival (OS) and disease-free survival. Of the 75 consecutive patients who received liver transplantation for treatment of HCCA, 62 patients were enrolled. Thirty-four patients were randomized in the chemotherapy group; 28 patients were in the control group and transplanted only. OS rates at 5 years were 38% in the chemotherapy group and 40% in the control group, disease-free survival rates at 5 years 43% and 53%, respectively. Tumor stage and vascular invasion were identified as independent risk factors for recurrence of disease. Doxorubicin chemotherapy did not improve organ survival and disease-free survival in patients undergoing liver transplantation for HCCA.  相似文献   
84.
85.
螺旋CT在小肾癌诊断中的价值   总被引:13,自引:2,他引:11  
目的评价螺旋CT多期扫描在小肾癌诊断中的价值。方法收集经手术病理证实的小肾癌14例,分析其螺旋CT平扫、皮质期、实质期及肾盂期的表现。结果CT平扫病灶呈等密度7例,稍低密度5例,稍高密度1例,1例为囊实性肿块,其中2例伴斑点状钙化。增强扫描皮质期12例呈明显强化,2例呈轻中度强化。肾实质期肿瘤密度迅速减退,肾盂期肿瘤密度进一步减退。结论小肾癌螺旋CT增强多期扫描征象有一定特征性,对小肾癌的诊断有重要价值。  相似文献   
86.
目的了解本地区甲状腺肿瘤的发病情况,探讨甲状腺肿瘤的诊断与鉴别诊断6方法对416例甲状腺肿瘤病理资料进行回顾性分析。结果甲状腺肿瘤以良性多见,良恶性之比为8.2:1。各类型肿瘤均以女性明显多于男性,男女之比为1:5.4,好发年龄为21~50岁,肿瘤发生于甲状腺右侧多见。结论本组甲状腺肿瘤的发生率、好发年龄、性别差异、良恶之比与文献报道基本一致。乳头状腺瘤与乳头状癌的鉴别有一定难度,对可疑标本要多处取材,连续切片,仔细观察,找出其特征,提高诊断的准确性。  相似文献   
87.
食管癌三维适形后程加速超分割放射治疗的疗效分析   总被引:3,自引:0,他引:3  
目的评价三维适形后程加速超分割放射治疗食管癌的疗效及放疗反应、并发症。方法2002年2月至2004年5月,71例食管鳞癌随机分成两组,三维适形后程加速超分割组36例,食管病变上下外约4cm,前后、左右外约0.5~1cm作为PTV1,每次2GY,每周5次,DT40GY后,病变上下外约2cm,前后、左右外约0.5~1cm作为PTV2,每日2次,每次1.5GY,间隔4~6小时,总疗程6周,总剂量67GY/38次。非三维适形后程加速超分割组35例,时间、剂量、分割方式同适形组。所有病例均采用8MV-X外照射。结果1、2、3年的生存率和原发肿瘤的局控率,与非适形后程加速超分割比较,适形组明显提高,分别为88.9%、75%、63.9%比68.6%、51.4%、40%和86.1%、72.2%、58.3%比65.7%、48.5%、34.3%。适形组的急性放射反应明显低于非适形后程加速超分割组,两组有显著差别。结论本研究的初步结果表明食管癌适形后程加速超分割放射治疗的疗效优于非适形后程加速超分割组。  相似文献   
88.
目的:探讨胃癌术后残胃无力的诊治及预防。方法:对1998年~2004年间284例胃癌术后出现的17(6%)例残胃无力患者进行回顾性研究。结果:残胃无力发生于术后6~15天,症状持续10~21天。经消化道造影确诊,用非手术方法治疗后症状全部消失。结论:消化道造影是可靠的诊断方法,非手术方法治疗效果肯定。  相似文献   
89.
Radiotherapy(RT)is an important ap-proach for treatment of esophageal carcinoma(EC),especially for patients who have missedthe chance of surgical section.The efficacy ofRTis not satisfactory for its1-year,3-year and5-year survival rates being merely50%,20%,and10%respectively(1).Researches in recent years showed thatbetter efficacy can be obtained by combiningRTwith Chinese herbal medicines for EC thatincapable to be resected.Kang ai Injection(康艾注射液,KAI)is a Chinese herbal prep-arati…  相似文献   
90.
Summary Nonmelanoma skin cancer (NMSC) is the most common malignancy occurring in white populations. It is currently becoming an important challenge in terms of public health management as the increasing incidence rates will probably have a tremendous impact on healthcare costs. Possible factors driving this rise in NMSC numbers are increases in both acute and prolonged UV exposure together with increasing numbers of older people in the population. A better understanding of NMSC epidemiology in Europe is essential if an evidence-based European-wide public health policy is to be developed. It is obvious this can only be achieved by recording and analysing comparative epidemiological data. Finally, by improving the skin examination training for physicians, developing guidelines and exchanging best practices, a high level of healthcare could be provided for NMSC.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号